Vol. 1.] 



Woodivortli. — Wing Veins of Insects. 



139 



To Comstock we are indebted for the fullest stud}- of the 

 venation of the Macro-lepidoptera, and to Spuler for the only 

 extensive comparative study of the Micro-lepidoptera. These 

 two authors are in essential agreement as to the homology of 

 the veins within the order, but they differ in regard to nomen- 

 clature and in the comparisons they institute with other insects. 

 There is a decided difference between the opinion of these later 

 writers and the older views held b}' the systematists as to the 

 relation between veins, though not in the determination of 

 homologies. 



Spuler considers Micropteryx as representing the most primi- 

 tive existing condition of venation, but Comstock supposes it 

 to be Hepialis. These two venations are really very similar, 



FIG. 93. Diagram iUustrating the vena- 

 tion of the .lugata'. Solid lines show con- 

 stants in Macropterygidfe, dotted lines the 

 variables. The venation in Hepialidse is 

 like the minimum venation of Macroptery- 

 gidie with the veins marked H in addition. 

 Vein marked HX occurs only in Hepialida-. 



FIG. 94. Diagram of the vena- 

 tion of Tineina. Solid lines are 

 constants, and dotted lines varia- 

 bles. 



as will be seen by examining the accompanying diagram (Fig. 

 93). In Hepialis the front and hind wings are a little mol*e 

 nearly alike and the resemblance to the venation of the Phry- 

 gangeidte a little more complete, so that we must agree with 

 Comstock in regarding this the more primitive form. 



The resemblance of the venation of these insects to that of 

 the Phryganffiidse is so perfect that there seems to be but little 

 doubt that there is a very close relationship between the two 

 groups. This idea is strengthened by the fact that in reduced 

 venations, such as occur in the Tineina, we see the same 

 method of reduction exhibited as that seen in the Phryganaei- 

 dse. (Compare Figs. 49 and 94.) If our determination of the 

 veins is right in the latter group, there will be no difficulty in 

 establishing the homologies in this case. 



One vein at the end of the discal cell has long been recognized 



